Systems and methods for filtering fuel

ABSTRACT

A manifold for a fuel filter assembly includes a first base, which may define a first inlet passage to direct flow to a first filter element, and a first outlet passage to direct flow from the first filter element to a second base. The manifold includes a second base, which may define a second inlet passage to receive flow from the first base and direct the flow to the second filter element, and a second outlet passage to receive the flow from the second filter element. The manifold includes a diverting module, which may provide flow communication between the first outlet passage and second inlet passage, such that flow in the first inlet passage passes through the first filter element before entering the second inlet passage. The first and second inlet passages may define a common longitudinal axis. The first and second outlet passages may define a common longitudinal axis.

TECHNICAL FIELD

This disclosure relates generally to systems and methods for filteringfuel, and more particularly, to systems and methods for directing fuelfiltration through modules receiving spin-on type fuel filters.

BACKGROUND

Engines, including compression-ignition engines, spark-ignition engines,gasoline engines, gaseous fuel-powered engines, and other internalcombustion engines, may operate more effectively with fuel from whichcontaminates have been removed prior to the fuel reaching a combustionchamber of the engine. In particular, fuel contaminates, if not removed,may lead to undesirable operation of the engine and/or may increase thewear rate of engine components, such as, for example, fuel systemcomponents.

Effective removal of contaminates from the fuel system of acompression-ignition engine may be particularly important. In somecompression-ignition engines, air is compressed in a combustion chamber,thereby increasing the temperature and pressure of the air, such thatwhen fuel is supplied to the combustion chamber, the fuel and airignite. If water and/or other contaminates are not removed from thefuel, the contaminates may interfere with and/or damage, for example,fuel injectors, which may have orifices manufactured to exactingtolerances and shapes for improving the efficiency of combustion and/orreducing undesirable exhaust emissions. Moreover, the presence of waterin the fuel system may cause considerable engine damage and/or corrosionin the injection system.

Fuel filtration systems serve to remove contaminates from the fuel. Forexample, some conventional fuel systems may include a primary fuelfilter, which removes water and large particulate matter, and asecondary fuel filter, which removes a significant portion of remaining(e.g., smaller) contaminates, such as fine particulate matter. Inparticular, a typical secondary filter may include multiple filterelements attached to a shared housing. The housing directs fuel flowthrough the filter elements and out to the fuel system. Multiple filterelements may be attached to the housing, such that a given volume offuel is filtered by only one of the multiple filter elements. Thus, in asystem including a primary filter and a secondary filter, a given volumeof fuel is filtered via filtration media twice—once in the primaryfilter, where water and relatively large particulate matter may beremoved, and once in the secondary filter, where relatively smallparticulate matter may be removed. In some systems, attempts to improvethe effectiveness of filtration systems have resulted in providingadditional, separate fuel filters arranged with a modified housing tosupplement the primary and secondary fuel filters. The complexmodification of the housing, however, may be undesirable due, forexample, to the increased number of components, requiring repair andregular maintenance, and introduction of potential additional leakpoints.

One attempt to modify the housing which receives a fuel filter isdescribed in U.S. Pat. No. 7,294,262 (“the '262 patent”) issued toTadlock on Nov. 13, 2007. Specifically, the '262 patent discloses amodular fluid treatment assembly and method in which modules of thesystem each have a head that can be connected to one or more heads (ofone or more modules) in different configurations. The modules may have ahead with substantially concentric inlet and outlet ports in fluidcommunication with a cartridge coupled to the head. Although the modularfilter assembly described in the '262 patent may benefit from itscapacity to connect one or more heads in different configurations, the'262 patent presents a system that includes a large number of parts,therefore providing additional complexity and potential leak points forfuel.

The present disclosure may be directed to overcoming or mitigating oneor more of the potential problems set forth above.

SUMMARY

In one aspect, the present disclosure is directed to a manifoldconfigured to direct fuel flow within a fuel filter assembly. Themanifold may include a first base. The first base may define a firstinlet passage configured to direct fuel flow to a first filter element,a first outlet passage configured to direct fuel flow from the firstfilter element to a second base, and a coupling configured to receivethe first filter element. The manifold may further include a secondbase. The second base may define a second inlet passage configured toreceive fuel flow from the first base and direct the fuel flow to thesecond filter element, a second outlet passage configured to receive thefuel flow from the second filter element, and a coupling configured toreceive the second filter element. The manifold may further include adiverting module operably coupled between the first base and the secondbase. The diverting module may be configured to provide flowcommunication between the first outlet passage and the second inletpassage, such that the fuel flow in the first inlet passage passesthrough the first filter element before flowing into the second inletpassage. The first inlet passage and the second inlet passage may definea common longitudinal axis, and the first outlet passage and the secondoutlet passage may define a common longitudinal axis.

An additional aspect of the present disclosure is directed to a filterassembly, which may include a first filter element configured to filterfuel, a second filter element configured to filter fuel, and a manifoldconfigured to direct fuel to the first and the second filter elements.The manifold may include a first base. The first base may define a firstinlet passage configured to direct fuel flow to at least one of thefirst filter element and the second filter element. The first base mayfurther include a first outlet passage configured to direct fuel flowfrom the first filter element to a second base, and a coupling receivingthe first filter element. The manifold may further include a secondbase. The second base may define a second inlet passage configured toreceive fuel flow from the first base and direct the fuel flow to thesecond filter element, a second outlet passage configured to receive thefuel flow from the second filter element, and a coupling receiving thesecond filter element. The manifold may further include a divertingmodule operably coupled between the first base and the second base. Thediverting module may be configured to provide flow communication betweenthe first outlet passage and the second inlet passage, such that thefuel flow in the first inlet passage passes through the first filterelement before flowing into the second inlet passage. The first inletpassage and the second inlet passage may define a common longitudinalaxis, and the first outlet passage and the second outlet passage maydefine a common longitudinal axis.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic illustration of an exemplary embodiment of a powersystem;

FIG. 2 is a schematic, perspective view of an exemplary embodiment of afuel filter assembly; and

FIG. 3 is a schematic, partial cross-section view of the exemplaryembodiment shown in FIG. 2.

DETAILED DESCRIPTION

FIG. 1 illustrates an exemplary embodiment of a power system 10configured to convert fuel and air into mechanical work. Power system 10includes an engine 12 (e.g., a four-stroke compression-ignition engine).One skilled in the art will recognize that engine 12 may be any type ofinternal combustion engine, such as, for example, a spark-ignitionengine, a gasoline engine, or a gaseous fuel-powered engine. Engine 12may include a block 14 that at least partially defines a plurality ofcombustion chambers 16. As shown in FIG. 1, exemplary engine 12 includesfour combustion chambers 16. It is contemplated that engine 12 mayinclude a greater or lesser number of combustion chambers 16, and thatcombustion chambers 16 may be disposed in any configuration, such as,for example, in an “in-line” configuration, a “V” configuration, or anyother known configuration. Engine 12 may include a crankshaft 18 that isrotatably disposed within block 14. Connecting rods (not shown) mayconnect a plurality of pistons (not shown) to crankshaft 18, so thatcombustion within a combustion chamber 16 results in a sliding motion ofeach piston within a respective combustion chamber 16, which, in turn,results in rotation of crankshaft 18, as is conventional in areciprocating-piston engine.

Power system 10 may include a fuel system 20 configured to deliverinjections of pressurized fuel into each of combustion chambers 16according to a timing scheme, resulting in coordinated combustion withincombustion chambers 16. For example, fuel system 20 may be a common railsystem and may include a tank 22 configured to hold a supply of fuel,and a fuel pumping arrangement 24 configured to flow and/or pressurizethe fuel and direct the fuel to a plurality of fuel injectors 26associated with combustion chambers 16 via a flow path 28 (e.g., a fuelrail).

For example, pumping arrangement 24 may include one or more pumpingdevices configured to increase the pressure of the fuel and direct oneor more pressurized streams of fuel to flow path 28. According to someembodiments, pumping arrangement 24 may include a low pressure pump 30and a high pressure pump 32 disposed in series and fluidly connected byway of a fuel line 34. Low pressure pump 30 may include a transfer pumpthat provides a low pressure fuel feed to high pressure pump 32. Highpressure pump 32 may receive a low pressure fuel feed and increase thepressure of the fuel up to as much as, for example, 300 MPa. Highpressure pump 32 may be operably coupled to flow path 28 via a fuel line36.

According to the exemplary embodiment shown in FIG. 1, low pressure pump30 and/or high pressure pump 32 may be operably coupled to engine 12 andmay be driven, for example, via crankshaft 18, either directly orindirectly. For example, low pressure pump 30 and/or high pressure pump32 may be operably coupled to crankshaft 18 in any manner known to thoseskilled in the art, such that rotation of crankshaft 18 will result in acorresponding driving rotation of low pressure pump 30 and/or highpressure pump 32. For example, a driveshaft 42 of high pressure pump 32is shown in FIG. 1 as being operably coupled to crankshaft 18 via a geartrain 44. It is contemplated, however, that low pressure pump 30 and/orhigh pressure pump 32 may alternatively be driven electrically,hydraulically, pneumatically, or in any other known manner. It isfurther contemplated that fuel system 20 may also include, for example,a mechanical fuel injector system and/or a hydraulic fuel injectorsystem, where the pressure of the injected fuel is generated and/orenhanced within individual injectors, with or without the use of a highpressure source.

According to some embodiments, one or more filtering assemblies, suchas, for example, a primary filter assembly 38 and/or a secondary filterassembly 40, may be disposed along fuel line 34 (e.g., in a seriesrelationship, as shown), and may be configured to remove contaminates,such as water and/or particulate matter from the fuel. For example,primary filter assembly 38 may include a filter element (not shown)configured to remove water and/or relatively large particulate matterfrom fuel received from tank 22. According to some embodiments,secondary filter assembly 40 may include one or more filter elementsconfigured to remove particulate matter from fuel that has not beenremoved via primary filter assembly 38 (e.g., relatively smallerparticulate matter), as described in more detail below. For example,primary filter assembly 38 may include a filter media configured toremove non-fuel liquid (e.g., water) and/or about 10 micron-size andlarger particles, and secondary filter assembly 40 may include a filtermedia configured to remove about 3 micron-size and larger particles.

According to the exemplary embodiment shown in FIG. 2, secondary filterassembly 40 may include, for example, one or more filter modules. Eachof the filter modules may include a filter base and a filter element.For example, the exemplary embodiment of secondary filter assembly 40shown in FIG. 2 includes a first filter module 46, including a firstfilter base 48 and a first filter element 50, a second filter module 52,including a second filter base 54 and a second filter element 56, and athird filter module 58, including a third filter base 60 and a thirdfilter element 62. One or more of the filter bases 48, 54, and 60defines a manifold 63 for secondary filter assembly 40. Filter elements50, 56, and 62 may be operably coupled to respective filter bases 48,54, and 60 in any manner known to those skilled in the art, such as, forexample via a threaded coupling. For example, one or more filterelements 50, 56, and 62 may be spin-on type fuel filters. According tothe exemplary embodiment shown in FIG. 2, one or more of filter elements50, 56, and 62 may include a semi-permeable filter media (not shown)configured to prevent particulate matter of relatively smallerparticulate size from passing through secondary filter assembly 40 tofuel injectors 26 (see FIG. 1). As shown in FIG. 2, exemplary secondaryfilter assembly 40 includes three modules 46, 52, and 58. It iscontemplated that secondary filter assembly 40 may be configured toinclude a greater or lesser number of modules, and thereby receive agreater or lesser number of filter elements.

One or more of modules 46, 52, and 58 may be mounted to engine 12, forexample, via a support structure (not shown). The support structure mayinclude any known configuration apparent to those skilled in the art.According to some embodiments, modules 46, 52, and 58 may be configuredto be removable from the support structure, thereby permittingreplacement or repair. As shown in FIG. 2, secondary filter assembly 40may include one or more bosses 64 configured to mount secondary filterassembly 40 to engine 12 or to other parts associated with engine 12.

As shown in the exemplary embodiment, modules 46, 52, and 58 may definesimilar exterior construction, and may be operably coupled to adjacentmodules. For example, filter bases 48, 54, and 60 may define a proximalend 66 and a distal end 68 configured to receive adjacent modules.According to the exemplary embodiment shown in FIG. 2, filter bases 48,54, and 60 may include a flange 70 at both proximal end 66 and distalend 68 and may be provided with one or more openings 72, configured toreceive a fastener 74, such as, for example, a bolt and/or a nut.

As shown in the exemplary embodiment, secondary filter assembly 40 mayinclude a diverting module 76. Diverting module 76 may be locatedbetween adjacent filter modules. Diverting module 76 may be operablycoupled between adjacent modules and provided with one or more openings(not shown) configured to receive one or more fasteners 74. For example,the exemplary embodiment of secondary filter assembly 40 shown in FIG. 2shows diverting module 76 located between second filter module 52 andthird filter module 58. According to some embodiments, diverting module76 may define similar exterior construction as flange 70, and may beconfigured to be removable from secondary filter assembly 40, therebypermitting replacement or repair. As shown in FIG. 2, exemplarysecondary filter assembly 40 includes one diverting module 76. It iscontemplated that secondary filter assembly 40 may include a greater orlesser number of diverting modules 76.

As shown in FIG. 3, filter bases 48, 54, and 60 may include a number ofpassages configured to direct the fuel flow through secondary filterassembly 40. For example, filter bases 48, 54, and 60, and divertingmodule 76 may be configured to direct the flow of fuel into and from twoor more filter elements in a parallel manner (i.e., such that a givenvolume of fuel is filtered via a single filter element), or in a seriesmanner (i.e., such that fuel is filtered via more than one filterelement prior to flowing out of secondary filter assembly 40). Accordingto the exemplary embodiment shown in FIG. 3, filter bases 48, 54, and 60may have similar internal arrangements and may be configured to directfuel flow through filter elements 50, 56, and 62 in a parallel flowarrangement. Diverting module 76 may have an internal arrangementconfigured to direct fuel flow through filter elements 50, 56, and 62 ina parallel or series flow arrangement. In a combined parallel and seriesflow arrangement, for example, as shown in FIG. 3, first and secondfilter modules 46 and 52 may be configured to direct flow in a parallelarrangement to diverting module 76. Diverting module 76 then directsfuel flow through third filter module 58, such that a given volume offuel received from fuel line 34 may be filtered by first filter element50 or second filter element 56, and is then directed through thirdfilter element 62 prior to flowing out of secondary filter assembly 40.

For example, first filter base 48 may be configured to direct fuel flowreceived from fuel line 34 (see FIG. 1) through first filter element 50,and output filtered fuel directly to third filter base 60 withoutpassing through filter element 56. Second filter base 54 may beconfigured to direct fuel flow received from fuel line 34 (see FIG. 1)through second filter element 56, and output filtered fuel directly tothird filter base 60. Diverting module 76 may be configured to directfuel flow through third filter base 60. Third filter base 60 therebyreceives filtered fuel from first and second filter elements 50 and 56,and directs the filtered fuel through third filter element 62, andoutputs the twice-filtered fuel to fuel line 36 and/or into highpressure pump 32 (see FIG. 1).

In the exemplary embodiment shown in FIG. 3, first filter base 48 maydefine an inlet 78, an inlet passage 80, a filter element inlet 82, afilter element outlet 84, an outlet passage 86, and an outlet 88. Inlet78 may be configured to receive fuel line 34 (see FIG. 1) via aconnection, such as, for example, a threaded fastener, press fitconnection, or any other connection known in the art. Inlet passage 80may be in flow communication with inlet 78, and may define a channelthat connects inlet 78 and filter element inlet 82. Filter element inlet82 may be configured within inlet passage 80, such that fuel flow tofilter element inlet 82 is directed through the filter media of firstfilter element 50. Outlet passage 86 may terminate at one end in outlet88 and may define a channel connecting filter element outlet 84 andoutlet 88. Filter element outlet 84 may be defined in outlet passage 86,which is configured to receive filtered fuel from first filter element50.

As shown in the exemplary embodiment, it is contemplated that firstfilter base 48 and second filter base 54 have a substantially similarinternal configuration. For example, second filter base 54 may define aninlet 90, an inlet passage 92, a filter element inlet 94, a filterelement outlet 96, an outlet passage 98, and an outlet 100. Inlet 90 ofsecond filter base 54 may be configured to receive fuel line 34 (seeFIG. 1) and/or may be in flow communication with inlet passage 80 offirst filter base 48 (see FIG. 3). Inlet passage 92 may be in flowcommunication with inlet 90 and may define a channel that connects inlet90 and filter element inlet 94. Filter element inlet 94 may be providedwithin inlet passage 92, such that fuel flow to filter element inlet 94is directed through the filter media of second filter element 56. Outlet100 may be located at proximal end 66 of second filter base 54, remotefrom inlet 90. Outlet passage 98 may terminate at one end in outlet 100and may define a channel connecting filter element outlet 96 and outlet100. Filter element outlet 96 may be defined in outlet passage 98, andmay be configured to receive filtered fuel from second filter element56.

As shown in the exemplary embodiment, it is contemplated that secondfilter base 54 and third filter base 60 have a substantially similarinternal configuration. For example, third filter base 60 may define aninlet 102, an inlet passage 104, a filter element inlet 106, a filterelement outlet 108, an outlet passage 110, and an outlet 112. Inlet 102of third filter base 60 may be configured to receive fuel line 34 (seeFIG. 1) and/or may be in flow communication with inlet passage 80 offirst filter base 48 and/or inlet passage 92 of second filter base 54.Inlet passage 104 may be in flow communication with inlet 102 and maydefine a channel that connects inlet 102 and filter element inlet 106.Filter element inlet 106 may be provided within inlet passage 104, suchthat fuel flow to filter element inlet 106 is directed through thefilter media of third filter element 62. Outlet 112 may be located atproximal end 66 of third filter base 60, remote from inlet 102. Outletpassage 108 may terminate at one end in outlet 112 and may define achannel connecting filter element outlet 108 and outlet 112. Filterelement outlet 108 may be defined in outlet passage 110, and may beconfigured to receive filtered fuel from third filter element 62.

In the exemplary embodiment shown in FIG. 3, diverting module 76 maydefine an inlet 114, a diverting passage 116, and an outlet 118.Diverting module 76 may be configured to prevent the flow of fuel fromthe inlet passage of a preceding filter module to the inlet passage of afollowing filter module. For example, diverting module 76 may beconfigured to prevent the flow of fuel from fuel line 34 via inletpassage 80 of first filter base 48, and/or from inlet passage 92 ofsecond filter base 54, from entering third filter module 58 until thefuel has been filtered by at least one of the filter elements associatedwith first module 46 and second module 52. For example, as shown in FIG.3, inlet 114 may be provided adjacent to outlet 100 of second filterbase 54, whereby inlet 114 may be configured to receive fuel flow fromoutlet 100. Diverting passage 116 may define a channel that connectsinlet 114 and outlet 118, such that filtered fuel flows from firstfilter module 46 and/or second filter module 52 through the filter mediaof third filter element 62 in third filter module 58.

It is contemplated that filter bases 48, 54, and 60, and divertingmodule 76 may be arranged in a linear configuration (i.e., in anend-to-end configuration), where inlet passage 80, inlet passage 92, andinlet passage 104 may define a common longitudinal axis. Similarly, itis contemplated that outlet passage 86, outlet passage 98, and outletpassage 110 may define a common longitudinal axis. Filter bases 48, 54,and 60, and diverting module 76 may include complimentary protrusions120 and recesses 122 to aid in alignment (FIG. 3). It is furthercontemplated that filter bases 48, 54, and 60 may include vent openings124. Vent openings 124 may be defined in a vent passage 126 along acommon longitudinal axis included in filter bases 48, 54, and 60, and/ordiverting module 76. Vent passage 126 may aid in the venting of vaporfrom filter elements 50, 56, and 62. Some embodiments of vent passage126 may include, for example, a portion configured to direct the flow offuel vapor is such a way as to create a pressure differential betweenpreceding and following vent passages 126. For example, as shown in FIG.3, diverting module 76 may include a portion 127 arranged to provideflow communication between an inlet 129 and an outlet 130, such that theflow area defined by outlet 130 is less than the flow area defined byinlet 129. For example, portion 127 may define a truncated conical shapebetween inlet 129 and outlet 130 (e.g., outlet 130 may define an orificehaving a 2 mm diameter).

Pumping arrangement 24 may direct one or more pressurized streams offuel into first filter base 48, and/or second filter base 54, via inlet78 and/or inlet 90. Inlet passage 80 and inlet passage 92 may beconfigured to direct fuel received from inlets 78 and 90, to filterelement inlets 82 and 94, respectively, along arrow A. Filter elementinlets 82 and 94 direct fuel flow to first filter element 50 and secondfilter element 56, respectively. Fuel may then flow through first filterelement 50 or second filter element 56, which capture particulate matterin the fuel (e.g., particulate matter not captured via primary filterassembly 38). After passing through first filter element 50 or secondfilter element 56, fuel is directed to filter element outlets 84 and 96,where outlet passages 86 and 98 direct fuel out of first and secondfilter bases 48 and 54 via outlets 88 and 100, along arrow B.

First filter base 48 and/or second filter base 54 may then direct apressurized stream of fuel into diverting module 76 via inlet 114.Diverting passage 116 may then direct fuel received from outlet 88 and100 to outlet 118, along arrow C. Diverting module 76 may then direct apressurized stream of fuel into third filter base 60 via inlet 102.Inlet passage 104 may then direct fuel received from inlet 102 to filterelement inlet 106, along arrow D, where filter element inlet 106 directsfuel flow to third filter element 62. The fuel may then flow throughthird filter element 62, which captures particulate matter in the fuel(e.g., particulate matter not captured via primary filter assembly 38and/or first filter element 50 and/or second filter element 56). Afterpassing through third filter element 62, fuel is directed to filterelement outlet 108, where outlet passage 110 directs fuel to outlet 112,along arrow E.

INDUSTRIAL APPLICABILITY

The fuel filter assembly of the present disclosure may be applicable toa variety of power systems, such as, for example, compression-ignitionengines, gasoline engines, gaseous-fuel-powered engines, and otherinternal combustion engines known in the art, for example, where thereduction of exhaust emissions and/or improved fuel efficiency, amongother things, may be desired. By virtue of using the disclosed fuelfilter assembly in association with a power system, more precise controlof fuel delivery may be achieved, thereby possibly reducing exhaustemissions and/or increasing fuel efficiency. Operation of exemplarypower systems provided with an exemplary fuel filter assembly will nowbe explained.

Referring to FIG. 1, a supply of fuel is drawn from tank 22 via pumpingarrangement 24. In the disclosed example, low pressure pump 30 and thehigh pressure pump 32 are disposed in series and are fluidly connectedby way of fuel line 34. Low pressure pump 30 may include a transfer pumpthat provides a supply of fuel at relatively low pressure to highpressure pump 32. High pressure pump 32 may receive the low pressurefuel and further increase the pressure of the fuel. One or morefiltering assemblies, such as primary filter assembly 38 and secondaryfilter assembly 40, may be disposed along fuel line 34 and may serve toremove undesirable fluid and/or particulate matter from the fuel. Fuelis drawn through fuel filter assembly 38 via high pressure pump 32and/or low pressure pump 30, where filter media removes fluid (e.g.,water) and relatively large particulate matter from the fuel.

After flowing through primary filter assembly 38, the fuel enterssecondary filter assembly 40, where the fuel undergoes additionalfiltration to remove particulate matter (e.g., relatively smallerparticulate matter) that was not removed via primary filter assembly 38.Referring to FIG. 3, the fuel is received at inlet 78 and is directedthrough inlet passages 80 and 92 to filter element inlets 82 and 94.Thereafter, filter element inlets 82 and 94 direct fuel flow to filterelements 50 and 56, respectively. Fuel then flows through the filterelements 50 or 56, which capture particulate matter in the fuel,providing a first filtration of particulate matter within secondaryfilter assembly 40. The fuel is then directed to filter element outlets84 and 96, where outlet passages 86 and 98 direct the fuel flow out offilter bases 48 and 54 via outlets 88 and 100, respectively. At thispoint, the fuel has been filtered in a parallel manner via first andsecond filter modules 46 and 52.

Via diverting module 76, fuel is then directed into third filter base60, where the fuel undergoes an additional filtration (i.e., a seriesfiltration). The filtered fuel received from filter bases 48 and 54 isdirected via diverting passage 116 to filter element inlet 106, wherefilter element inlet 106 directs fuel flow through third filter element62. The fuel flows through the third filter element 62, which capturesparticulate matter in the fuel that was not captured via primary filterassembly 38 and/or first filter element 50 and/or second filter element56. The filtered fuel is then directed to filter element outlet 108,where outlet passage 110 directs fuel to outlet 112 and out of secondaryfilter assembly 40. The filtered fuel then flows to flow path 28 (e.g.,a fuel rail) via fuel line 36 and high pressure pump 32. The filteredfuel may then be supplied to combustion chambers 16 via fuel injectors26, and the filtered fuel, along with air, may be ignited, therebyproducing mechanical work.

The disclosed fuel filter assembly may ensure more complete removal ofparticulate matter and/or non-fuel fluids from fuel and may providerelatively compact packaging for use in machine environments havingrelatively limited space. Specifically, directing fuel flow throughmultiple filter elements arranged in series by diverting the fuel flowby the addition of a component that mates to existing filter baseconfigurations may result in enhanced fuel filtration without requiringadditional space and redesign cost. Embodiments where neithermanufacturer nor consumer are not required to undertake major retoolingor machine reconfiguration while improving product performance allow forincreased likelihood that such efficiency updates will be made. Utilizedin conjunction with a primary fuel filter assembly, fuel passing throughthe disclosed filter assembly may be filtered at least three times priorto entering injectors.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the disclosed, exemplarypower system and/or fuel filter assemblies. Other embodiments will beapparent to those skilled in the art from consideration of thespecification and practice of the disclosed examples. It is intendedthat the specification and examples be considered as exemplary only,with a true scope being indicated by the following claims and theirequivalents.

1. A manifold for a filter assembly, the manifold comprising: a firstbase defining a first inlet passage configured to direct fuel flow to afirst filter element, a first outlet passage configured to direct fuelflow from the first filter element to a second base, and a couplingconfigured to receive the first filter element; a second base defining asecond inlet passage configured to receive fuel flow from the first baseand direct the fuel flow to the second filter element, a second outletpassage configured to receive the fuel flow from the second filterelement, and a coupling configured to receive the second filter element;and a diverting module coupled between the first base and the secondbase, the diverting module being configured to provide flowcommunication between the first outlet passage and the second inletpassage, such that the fuel flow in the first inlet passage passesthrough the first filter element before flowing into the second inletpassages, wherein the first inlet passage and the second inlet passagedefine a common longitudinal axis, and wherein the first outlet passageand the second outlet passage define a common longitudinal axis.
 2. Themanifold of claim 1, wherein the first base, the second base, and thediverting module define at least one of protrusions and recessesconfigured to align the first base, the second base, and the divertingmodule with respect to one another.
 3. The manifold of claim 1, whereinthe first base and the second base define at least one flange configuredto couple the first base, the second base, and the diverting module toone another.
 4. The manifold of claim 1, wherein at least one of thefirst base and the second base includes a boss configured to couple themanifold in operational relation to an engine.
 5. The manifold of claim1, wherein the first base, the second base, and the diverting moduleeach define a vent passage configured to permit flow of vapor from atleast one of the first filter element and the second filter element, andwherein the vent passages define a common longitudinal axis.
 6. Themanifold of claim 1, further including a third base coupled to the firstbase, the third base defining a third inlet passage configured to directfuel flow to at least one of a third filter element and the first inletpassage, a third outlet passage configured to direct fuel flow from thethird filter element to at least one of the first base and the secondbase, and a coupling configured to receive the third filter element,wherein the third inlet passage and the first inlet passage define acommon longitudinal axis, and wherein the third outlet passage and thefirst outlet passage define a common longitudinal axis.
 7. A filterassembly comprising: a first filter element configured to filter fuel; asecond filter element configured to filter fuel; and a manifoldconfigured to direct fuel to the first and the second filter elements,the manifold including a first base defining a first inlet passageconfigured to direct fuel flow to at least one of the first filterelement and the second filter element, a first outlet passage configuredto direct fuel flow from the first filter element to a second base, anda coupling receiving the first filter element; a second base defining asecond inlet passage configured to receive fuel flow from the first baseand direct the fuel flow to the second filter element, a second outletpassage configured to receive the fuel flow from the second filterelement, and a coupling receiving the second filter element; and adiverting module coupled between the first base and the second base, thediverting module being configured to provide flow communication betweenthe first outlet passage and the second inlet passage, such that thefuel flow in the first inlet passage passes through the first filterelement before flowing to the second filter element, wherein the firstinlet passage and the second inlet passage define a common longitudinalaxis, and wherein the first outlet passage and the second outlet passagedefine a common longitudinal axis.
 8. The filter assembly of claim 7,wherein the first filter element is configured to remove particulatematter having a first size greater than a first size dimension, and thesecond filter element is configured to remove particulate matter havinga second size greater than a second size dimension, and wherein thefirst size dimension and the second size dimension are about equal. 9.The filter assembly of claim 7, wherein at least one of the first filterelement and the second filter element includes a spin-on type fuelfilter.
 10. The filter assembly of claim 7, wherein the first base, thesecond base, and the diverting module define at least one of protrusionsand recesses configured to align the first base, the second base, andthe diverting module with respect to one another.
 11. The filterassembly of claim 7, wherein at least one of the first base and thesecond base defines at least one flange configured to couple the firstbase, the second base, and the diverting module to one another.
 12. Thefilter assembly of claim 7, wherein at least one of the first base andthe second base includes a boss configured to couple the manifold inoperational relation to an engine.
 13. The filter assembly of claim 7,wherein the first base, the second base, and the diverting module eachdefine a vent passage configured to permit flow of vapor from at leastone of the first filter element and the second filter element, andwherein the vent passages define a common longitudinal axis.
 14. Thefilter assembly of claim 7, further including a third base coupled tothe first base, the third base defining a third inlet passage configuredto direct fuel flow to at least one of a third filter element and thefirst inlet passage, a third outlet passage configured to direct fuelflow from the third filter element to at least one of the first base andthe second base, and a coupling receiving the third filter element. 15.A fuel system comprising: a tank configured to contain a supply of fuel;a low pressure pump configured to route the supply of fuel to a highpressure pump; a high pressure pump configured to raise the pressure ofthe supply of fuel; a primary fuel filter assembly including a primaryfilter element configured to remove at least one of undesired fluid andparticulate matter from the supply of fuel; and a secondary fuel filterassembly comprising a first filter element configured to filter fuel; asecond filter element configured to filter fuel; and a manifoldconfigured to direct fuel to the first and the second filter elements,the manifold including a first base defining a first inlet passageconfigured to direct fuel flow to at least one of the first filterelement and the second filter element, a first outlet passage configuredto direct fuel flow from the first filter element to a second base, acoupling receiving the first filter element, and a second base defininga second inlet passage configured to receive fuel flow from the firstbase and direct the fuel flow to the second filter element, a secondoutlet passage configured to receive the fuel flow from the secondfilter element, and a coupling receiving the second filter element, anda diverting module coupled between the first base and the second base,the diverting module being configured to provide flow communicationbetween the first outlet passage and the second inlet passage, such thatthe fuel flow in the first inlet passage passes through the first filterelement before flowing to the second filter element, wherein the firstinlet passage and the second inlet passage define a common longitudinalaxis, and wherein the first outlet passage and the second outlet passagedefine a common longitudinal axis.
 16. The fuel system of claim 15,wherein the first base, the second base, and the diverting module defineat least one of protrusions and recesses configured to align the firstbase, the second base, and the diverting module with respect to oneanother.
 17. The fuel system of claim 15, wherein at least one of thefirst base and the second base defines at least one flange configured tocouple the first base, the second base, and the diverting module to oneanother.
 18. The fuel system of claim 15, wherein at least one of thefirst base and the second base includes a boss configured to couple themanifold in operational relation to an engine.
 19. The fuel system ofclaim 15, wherein the first base, the second base, and the divertingmodule each define a vent passage configured to permit flow of vaporfrom at least one of the first filter element and the second filterelement, and wherein the vent passages define a common longitudinalaxis.
 20. The fuel system of claim 15, further including a third basecoupled to the first base, the third base defining a third inlet passageconfigured to direct fuel flow to at least one of a third filter elementand the first inlet passage, a third outlet passage configured to directfuel flow from the third filter element to at least one of the firstbase and the second base, and a coupling receiving the third filterelement.